Screen for wells



March 13, 1945. c 1. HAYNES j 2.371 391 SCREEN FOR WELL Filed Jan, 2,194

,W VI Q I jay/ 4% A TTOR/VEX means which allows the drill Patented 1-3,1945, I

Cecil J. Haynes, Houston, Tex.-, assignor Stand 1 ard Oil DevelopmentCompany, a corporation of Delaware Application-January 2, 1943, SerialNo; 411,101

3 Claims.

The present invention is directed to a device suitable for applicationto gravelpacked .wells or for use in the gravel packing of wells.

The present invention may be described briefly as comprising a screenswivelly attached to the lower end of a string of tubing with a. spiralconveyor arranged around the screen and secured to the tubing forrotation therewith.

This arrangement allows the screen to be forced into a pack of gravelafter the gravel has been placed in the well. Another use of the deviceis for agitating the gravel pack to sift the gravel and open cloggedportions of the .screen' 7 by rotating the spiral without allowinglongitudinal movement ofthe tubing. ,The device of the present inventionis also suitable for use in placing gravel, as for example, whenemploying the device shown in Patent 2,224,538, issued Dec. 10, 1940, toJohn E. Eckel et al. and entitled "Method and apparatus forgravel-packing wells, in which case it is desirable for the screwconveyor to be used to force the discharged gravel downward anddistribute it around the screen.

Other objects and advantages of the present invention may be seen from aeading of the following description taken with he drawing, in

which- Fig. 1 is a front elevation of a preferred embodiment of thepresent invention;

Fig. 2 is a view, .partlyin section, of a portion of the device shownin- Fig. 1 with the spiral conveyor removed therefrom;

Fig. 3 is a view of the parts not shown in Fig. 2 used to make up thecomplete unit illustrated in Fig. 1;

Fig. 4 is a view along IV--IV of Fig. 3; and

Fig. 5 is an elevation of an embodiment similar to that shown in Fig. 1,but with the spiral conveyor reversed for use in distributing gravel ingravel packing wells. A wire screen or perforated pipe ll is secured tothelower end of tubing or drill pipe II by respect to the screen. Asuitable means for at- 'taching the screen and tubing is illustrated inretained between them.

A rod l6 extending from the lower portion of pack and which prevents therotation of the screen II when tubing I2 is being rotated withoutlongitudinal movement. v

The remainder of the assembly as shown in Fig. 3 consists ofa-spider l1,helical flanges l8, and tip J9; The helical flanges areisecured to thetip by suitable means, such as by welding.

, A central passage extendsthrough the tipto allow the tip to bejournaled on rod IS. The

upper end of spider l"| forms a collar closely embracing tubing l2 andarranged to be secured thereto by. suitable means, such as set screw 2|.The lower portion of spider I1 is of substantially the same diameter asthehelical flanges and is provided with suitable screw threads 22 tocooperate with screw threads 23 formed on an annulus 24, to which theupper ends of the helical pipe to swivel with 1 the screen has securedthereto an anchor l6.

The anchor may be described briefly as formed of a sheet of metal with adownwardly extending knife edge which moves ahead of the screen while itis being forced down through a gravel flanges are attached.

Itwill be understood that there is appreciable clearance between membersI! and screen H.

It'als'o will be seen from the drawing that below The flanges rotatewith tubing l2, while the innor screen It may be held stationary by an-If a pack of gravel has been placed in the lower end of a borehole andit is desired to insert the tool of the present invention into the pack,the tubing with the tool secured to the lower end thereof may be loweredinto the borehole until it engages the upper portion of the pack. Theweight of the tubing may then be allowed to rest on the tool, whereuponrotation of the tubing will cause a corresponding rotation of flanges l8and the tapering lower, portion of the flanges will serve to lift thegravel or sand up and along the outside of the screen.

The flanges will remove the gravel or sand from immediately below thescreen and transport it to the top of this screen, thereby allowing thescreen to move downward into the gravel Back.

After the tool is placed as above described proauction may be obtainedthrough the screen in the usual manner. If at a y later date the packhas become contaminatedand openings in the pack and screen cloggedbyparamn or similar material, the gravel pack may be agitated to renovatethe gravel pack. This may be done by rotating tubing l2 without allowinglongitudinal movement of the tubing; gravelfrom adjacentthe lowerportion of the screen and forces it upwardly, at the same time.

This rotation lifts cleaning the screen by the relative rotation betweenmembers l8 and the outer surface of this 7 screen.

Another use of the device of the present ini vention is in placinggravel in the borehole by use of normal circulation, as described in U.S. Patent No. 2,224,538. In the above mentioned patent, the gravel isdeposited in the well by releasing it through a valve at the top of theliner and allowing it to settle downwardly under the influence ofgravity. When employing the tool for placing gravel, the spiralflanges-should be arranged so that rotation of the drill pipe will forcethe flanges to carry the gravel downwardly. Since it is the usualpractice to'have right-hand threads on the drill pipe, it is desirableto arrange the flanges as illustrated in Fig. 5 of the drawing.

- By attaching the tool illustrated in Fig. 5 to the lower end ofthe'tubing and releasing the gravel from the tubing above the screen,the rotation of the tubing causes the conveyor .to carry the graveldownwardly and positively form a uniform gravel pack. The advantage ofusing the tool described in the present application for depositinggravel is that it prevents bridging of the gravel and insures theformation of a gravel pack'without cavities.

Having fully described and illustrated preferred embodiments of thepresent invention, what I desire to claim is: V

1. A borehole tool comprising, in combination,

a screen adapted to be secured to the lower end of a string of tubing,means arranged to connect swiveily the screen to said tubing, an anchorsecured to said screen, and a spiral conveyor arranged over said screenand attached to said tubing for rotation therewith.

2. A borehole device comprising, in combination, a well screen, meansswivelly securing the upper end of said screen to the lower end of astring of tubing, an anchor secured to the lower end of said screen, anda member secured to the lower end of the tubing concentric with saidscreen and extending the length of the screen, whereby said member maybe given annular movement with respect to said screen.

3. A borehole tool adapted to be secured to the lower end of a string oftubing comprising, in combination, an elongated screen, means swivellyconnecting the upper end of said screen to the lower end of said stringof tubing, a flat sharpedged anchor, a rod extending along the longi-'tudinal axis of said screen having its upper end secured to the lowerend of said screen and its lower end secured to said anchor, a conveyorarrangedover said screen with the portion adjacent the screen helicaland its lower end extending below said screen and tapering inwardly, andmeans securing said conveyor to the lower end of said tubing forrotation therewith.

CECIL J. HAYNES.

